Introduction. Lipopolysaccharide, the endotoxin present in the cell wall of gram negative bacteria, is known to produce renal and liver toxicity. Endotoxin tolerance is a state in which prior exposure to low-dose lipopolysaccharide )LPS( induces resistance to subsequent LPS attack. This phenomenon has been widely studied in myocardial and brain tissues. In the present study, we aimed to investigate the protective effects of pretreatment with low dose lipopolysaccharide )LPS( on LPS- induced liver and kidney oxidative stress status.